Saltbush for Saline Land

Note Number: AG1294
Published: September 2007
Updated: June 2009

 

Saltbush is a native, salt-tolerant forage more suited to the warm climate and low rainfall areas of northern and central Victoria. It can be used to rehabilitate Class 2 (moderate) and Class 3 (severe) salt-affected soils that do not waterlog.

The most commonly used species are Old Man Saltbush (Atriplex nummularia) and River Saltbush (Atriplex amnicola). Old Man Saltbush is suited to well-drained areas and is relatively frost hardy. River Saltbush is more palatable and tolerant of slightly wetter areas.

Neither type is suitable for areas dominated by Samphire, which is an indicator of high levels of salinity and water logging, and that conditions may be too wet for Saltbush to persist.

Saltbush requires a combination of both warm temperatures (>25°C) and moderate moisture for its growth, so it is less suited to most areas in southern Victoria.

With good management, Saltbush can be a productive part of a grazing enterprise. Stands on less-saline areas can provide an opportunity to increase productivity by including inter-row species, such as medics. Land class or saline zone fencing to provide effective livestock control is a key to the success of saline rehabilitation with Saltbush.

Why use Saltbush?

Land clearing following European settlement has caused the watertable to rise across much of northern Victoria. In areas where water tables are within 2 m of the surface, moisture can rise to the surface and evaporate, concentrating salts at the surface. Salt-sensitive vegetation is killed by the salt, and the area becomes dominated by salt-tolerant plants such as Sea Barley Grass. Increasing levels of salts cause patches of bare ground known as scalds.

Saltbush stops this process by using moisture from deeper in the soil profile, lowering the watertable and disrupting the upward movement of moisture. Winter rainfall then leaches salts into the soil. The top soil becomes less saline and can support more salt-sensitive forage plants, such as medics.

Is the site ‘hostile’ or ‘reclaimable’?

Hostile sites have high levels of salinity and generally have a patchy cover of Sea Barley Grass, with scalds exceeding 1 m 2 (Class 3 salinity). They tend to occur when the rainfall is less than 400 mm, and on heavy soils, such as clays and clay loams. These sites can be planted to Saltbush primarily, with an optimum plant density of 2,000 stems/ha or more.

Reclaimable sites have moderate levels of salinity and generally have a thick cover of Sea Barley Grass with scalds less than 1 m 2 (Class 2 salinity). They tend to occur in the 400-600 mm rainfall zone and on lighter soils, such as sands and sandy loams. These sites should be planted to widely spaced rows of saltbush at a density of up to 1,500 stems/ha

On reclaimable sites, the areas between the rows of Saltbush can be sown to moderately salt-tolerant forage, species such as Tall Wheat Grass, Puccinellia and a salt-tolerant cultivar of Yellow Burr Medic (Medicago polymorpha cv Scimiter), and then fertilised with phosphate fertiliser. Saltbush will also benefit from fertiliser.

Establishment

Saltbush can be established by either direct seeding or planting nursery stock. Direct seeding requires exact and prescriptive conditions to minimise the risk of failure. Planting nursery stock is more expensive, but more reliable. Both forms of establishment require good preparation to minimise the risk of failure.

The site should be spraytopped in the spring prior to planting then ripped and mounded during summer to provide a seedbed. After autumn and early winter rains have leached salts out of the mounds, weeds should be sprayed and the seedlings planted in late winter or spring.

Grazing and management

Fencing to control livestock is the single most important tool for the management of saline discharge areas and Saltbush plantations. Samphire zones should be fenced to exclude livestock altogether. Saltbush needs to be fenced so that livestock can be made to strategically graze the stands.

The first grazing of a new stand can promote multiple stems and bushy growth and should only occur after the Saltbush is firmly anchored to the soil by its roots. This may be as early as eight months, but is generally 12-18 months after planting. Grazing must be closely monitored to ensure plant stems are not seriously damaged while they are young and fresh. Let livestock remove up to 80% of the leaves.

Mature Saltbush requires grazing once or twice a year to remain productive. Saltbush must be grazed hard to promote fresh growth.

Autumn is the most common time to graze Saltbush . The combination of understorey with Saltbush can raise the total feed value to a maintenance level. The stand can also be grazed in spring if productive species are planted between rows.

Saltbush leaves have a high salt concentration (up to 30% of dry weight). Sheep can only consume up to 200 grams of salt per day and, consequently, cannot eat enough Saltbush to maintain weight. A productive pasture between the Saltbush rows means stock can eat more and maintain weight. Supplementary feeding is required in Saltbush stands without any inter-row pasture.

Livestock grazing Saltbush must have access to fresh water.

Of the many varieties available, Old Man Saltbush is the most suitable for planting in saline discharge areas. It is deep-rooted and tolerant of both high salinity levels and low rainfall. Old Man Saltbush stands should be productive for 10-20 years, but can survive for up to 50 years depending on management.

Is saltbush for me?

Target area is in northern Victoria and experiences long hot summers	Suitable
Target area is Class 2 and 3 salinity (sea barley grass and bare patches)	Suitable
Surface soil only occasionally appears moist in summer	Suitable
Occasional samphire plants are present	Suitable for River Saltbush
Surface soil often appears moist in summer	Not suitable
Native species dominate the area	Not suitable
Target area is dominated by Samphire	Not suitable

 

 

References

• Barrett-Lennard E.G. (2003) Saltland Pastures in Australia. A Practical Guide. Second Edition. Land and Water Australia, Canberra, Australia
• Department of Agriculture and Food West Australia Farmnote 74/2004 Saltland pastures for the South Eastern Wheatbelt
• Saltland Pasture Association

Further information

• Western Australian Farmnote ‘ Saltbush establishment on saline sites’
• Western Australian Farmnote ‘The optimal design for saltbush’
• Saltbush establishment Collins J.P. (2007) Dept of Agriculture and Food West Australia Farmnote on saline sites (in press)
• The Optimal design for saltbush Collins J.P. (2007) Dept of Agriculture and Food West Australia Farmnote (in press)
• Land, Water & Wool and Australian Wool Innovation, 2006. SALTdeck Series, prepared for the Sustainable grazing on saline lands (SGSL) sub-program.
• Saltland Solutions – options for saltland restoration

Land and Water Australia 2009

Contacts

Greg Antonoff Farm Services Victoria Department of Primary Industries Horsham Victoria 3400 Phone 0353622111	Rob Sonogan Farm services Victoria Department of Primary Industries 324 Campbell Street Swan Hill Victoria 3585 Phone 0350364804
Wimmera Native Nursery 165 Lloyd St . Dimboola Vic 3414 Ph. (03) 5389 1193	Lloyd Naylor Grower and contract planter Pyramid Hill Vic 3575 Ph. (03) 5455 7327
Topline Plant Company PO Box 41 Uraidla SA 5142 Ph. (08) 8390 3369 Fax. (08) 8390 3603	Saltbush Australia PO Box 2105 Wagga Wagga NSW 2650 Ph. 1300 761 423
Grazing Management Systems Andew Sippel Narromine NSW 2821 Ph. (02) 6889 4300	D&B Starrick Contract planter Antwerp Vic 3414 Ph. (03) 5397 5256

Acknowledgements

This work was made possible through the collaborative support of Land, Water and Wool (through the Sustainable Grazing on Saline Lands sub-program), the Victorian Department of Primary Industry and the Cooperative Research Centre for Plant-based Management of Dryland Salinity (CRC Salinity). ‘Land, Water and Wool’ is a partnership between Australian Wool Innovation Pty. Ltd. and Land & Water Australia, with additional funding from Meat & Livestock Australia.

The editor and authors would also like to acknowledge the valuable contributions to these Agnotes made by:

• Ms Kim Bege – Media/Communications Officer Department of Primary industries Hamilton for invaluable assistance with layout of the final copy.
• Ms Anne Burgi of SUBStitution Pty Ltd Melbourne, for provision of expert professional editorial services.
• Ms Fiona Conroy for invaluable assistance with ensuring clarity of content and consistency of writing style.

This Agnote was developed by Greg Antonoff and Malcom McCaskill, September 2007.

It was reviewed by Greg Antonoff and Malcom McCaskill - Farm Services Victoria, June 2009.